The present invention relates generally to a processor-controlled multi-function general purpose radio frequency (RF) signal measurement and test instrument and, more particularly, to an integrated RF signal interface which couples RF signals between a plurality of test instruments, all of which are common to a single measurement and test instrument, and to external user equipment.
With the availability of sophisticated microprocessors, instrumentation designers have found it both possible and practical to integrate, within a single instrument, separate electronic devices which perform multiple, substantially independent functions. In the field of electronic measurement and test instrumentation, this has been more the rule than the exception in recent years. Electronic measurement and test instruments are now available which perform multiple, separate measurement and test functions with all the circuitry necessary to carry out those functions housed in a single chassis.
Previous attempts to integrate multiple test instruments into a single, general purpose measurement and test instrument have resulted in substantial complexity in the RF interface between the instrument and the external user equipment under test. It has been a technical challenge to instrumentation designers to provide an interface between equipment under test and test instrumentation which would allow a wide range of possible measurements without introducing additional and complex requirements for additional pieces of instrumentation, such as attenuators, for coupling test signals. Further, because of such complex interfaces, potential cost and functional benefit gain from integrated, general purpose test instrumentation is often lost or achieved only at additional cost for required signal coupling blocks and user extensive education of efficient use.